1. Field of the Invention
The present invention relates to a control system for an assembled battery.
2. Description of the Related Art
For a battery (an assembled battery) that consists of a plurality of cell groups connected together, each of these cell groups including a plurality of cells (unit cells) connected in series, a control system is per se known that is provided with a cell controller that monitors the states of the cells in each of the cell groups (for example, refer to Japanese Laid-Open Patent Publication 2005-318750). In this type of assembled battery control system, a bypass current flow circuit is provided that reduces differences in SOC (State Of Charge) between the cells that may arise during charging or discharging or due to neglect by flowing a bypass current in those cells whose SOCs are high, and that measures the no-load voltages and flows bypass current in those cells whose no-load voltages are high, thereby performing control so as to make the SOCs of all of the cells uniform.
However since, with the prior art control system for an assembled battery described above, in order to enhance the reliability, the detection circuit that detects the voltages of the cells is typically provided as a double system, i.e. is duplicated, accordingly the system becomes complicated due to increase in the number of components, and there is the problem of high cost.